English

Abstract

Whitefly, Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae), is a notorious sucking insect pest of cotton and many other crops worldwide. It acts as a vector of various diseases and responsible for causing destruction to economy by damaging major crops. In order to determine, the resistance ratio and efficacy of insecticides against whitefly, field populations of B. tabaci were collected from four districts (Multan, Bahawalpur, Jhang and Toba Tek Singh) of Punjab, Pakistan, during 2020 to 2022. After collection, leaf-dip bioassay method was used to measure resistance level in whitefly populations by insecticides (spirotetramat, buprofezin, pyriproxyfen, diafenthiuron, and bifenthrin). The results showed that B. tabaci developed high to very high resistance against buprofezin (97.26-108.41 fold), high resistance level against bifenthrin (70.65-95.30 fold), moderate to high resistance against pyriproxyfen (35.68-80.46 fold), moderate level of resistance against diafenthiuron (20.72- 30.77 fold), low level of resistance against spirotetramat (11.66-18.60 fold), while comparing with susceptible population. The results of present study i.e., spirotetramat and diafenthiuron may be used as wise choices regarding the selection of insecticides against B. tabaci and delay insecticide resistance